THE DIAGNOSIS AND PROPHYLAXIS OF THE IRON DEFICIENCY ...

JURNALUL PEDIATRULUI – Year XIV, Vol. XIV, Nr. 53-54, january-june 2011
THE DIAGNOSIS AND PROPHYLAXIS OF
THE IRON DEFICIENCY AND IRON DEFICIENCY
ANEMIA IN BABIES AND SMALL CHILDREN
Carmen Elena Niculescu¹, Ileana Puiu¹, Laura Marinău¹, D Niculescu², Eleonora Iordache¹
Abstract
The work refers to the diagnosis and prophylaxis of the
iron deficiency and iron deficiency anemia in babies
(naturally or artificially fed) and the children younger than 3
years. The recent studies show that iron deficiency anemia
and iron deficiency without iron deficiency can have long
term effects on neurological development. We hereby
present the adequate iron addition and the screening of iron
deficiency anemia.
Key words: iron deficiency, iron deficiency anemia, baby,
small child, iron addition
Introduction
The iron deficiency and iron deficiency anemia
continue to be a world health issue in the developing nations
and even in the industrialized ones (2,23,28). Nevertheless,
even more important than anemia is the iron deficiency
without anemia which can have long term effects on the
neurological development and behavior, some of them
irreversible. This work refers to the diagnosis and
prophylaxis of iron deficiency anemia.
Definition, prevalence and necessary iron
Anemia is defined as the drop in concentration of the
hemoglobin under 11g/dL in children aged between 12 and
36 months. In certain populations (such as the ones leaving
at high altitudes) the value adjustment must be done.
The normal iron concentration is the situation in which
there is enough iron to maintain the physiological functions
within normal limits. The iron deficiency is the situation in
which there is not enough iron to maintain the physiological
functions within normal limits. The iron deficiency is the
result of the inadequate absorption of iron reported to the
needs or of the negative balance of iron on long term. Each
of these situations leads to the decrease in the iron deposits
measured in serum ferritin or in the iron concentration in the
bone marrow. The iron deficiency may or may not be
accompanied by iron deficiency anemia. The iron deficiency
anemia is the anemia resulting from the iron deficiency
(2,16,18).
The iron overload is the excessive accumulation of iron
in the tissues. The iron overload is usually the result of the
genetic predisposition to excessively absorb and store iron
(e.g. hereditary hemochromatosis). The iron overload may
also be a complication in other hematologic diseases that
need repeated blood transfusions, repeated iron injections or
excessive iron ingestion.
The recommended iron diet is the average of the daily
iron needs that is enough for almost all individuals, based on
age and gender. The adequate iron need is the term used
when there is not enough information to establish the
recommended diet for certain population segments
(newborns, babies younger than 6 months)
80% if the iron quantity of the new born at birth is
formed during the last pregnancy trimester. The premature
newborn “skips” this period and has an iron deficiency.
Certain diseases of the mother, such as anemia, sugar
diabetes, arterial hypertension with in-uterus growth
deficiency, can lead to low iron deposits in the newborns
born on time, as well as the premature ones. The iron
deficiency in premature babies increases with the decrease
of the gestational age and is worsened by the frequent
phlebotomies without adequate blood replacement. On the
other hand the premature babies who receive multiple blood
transfusions run the risk of iron overload. The varying status
in blood in premature babies, with the risk of iron deficiency
or toxicity, makes the determination of the exact needs
impossible, which is estimated at 2-4 mg/day if administered
orally (1,12,28).
IOM (Institute of Medicine), taking into account the
average iron content of the human milk, has determined the
adequate intake at 0.27 mg/day in full term newborns since
birth until 6 months of age (16).
The average of the iron content of the human milk if
0.37 mg/L and the average of the milk needs of the
exclusively fed baby is estimated at 0.78 L/day. From these
valued the necessary amount has been determined at 0.27
mg/day for the full term newborn until 6 months of age.
IOM has considered that there must be a direct connection
between the age of the baby and the milk ingestion; thus
there must not be any correlation based on weight.
Nevertheless, there is a large variation in the iron
concentration in human milk and there is no guarantee that it
will cover the needs of the baby. For the babies between 6
and 12 months the recommended diet for iron (according to
IOM) is of 11 mg/day (16).
¹Pediatric Department, University of Medicine and Pharmacy Craiova
²Orthopedy and Traumatology Department, University of Medicine and Pharmacy Craiova
E-mail: niculescudragos@yahoo.com, vipuiu@yahoo.com, marinau_doru@yahoo.co.uk, niculescudragos@yahoo.com,
eleonora_iordache2@yahoo.com
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JURNALUL PEDIATRULUI – Year XIV, Vol. XIV, Nr. 53-54, january-june 2011
The amount of iron losses – the epithelial exfoliation of
the skin, the urinary and digestive tracts – was added to the
amount of the iron needs for the increase of the blood
volume with the growth of tissue mass and to the iron
deposits of that period. It is mentioned that the necessary
iron in babies does not pass directly from 0.27 mg/day to 11
mg/day at the age of 6 months. It is obvious that the full
term healthy newborn needs very little iron in the first 6
months as compared to the needs after 6 months (16,25).
Using the same reasoning, IOM considers that that
recommended necessary iron for the child aged 1-3 is of 7
mg/day.
There is no national statistic on the prevalence of iron
deficiency and iron deficiency anemia in babies. The general
prevalence in the USA of iron deficiency anemia has
dropped in babies and small children since the 1970s, with
the use of iron-enriched milk formulae and with the drop of
the use of cow milk in babies (2). Related the iron
deficiency anemia is the issue of the interaction between
iron and led. If the studies made on animals and humans it
has been noticed that the iron deficiency anemia increases
the intestinal absorption of led. Thus, iron deficiency anemia
decreases the efficiency of lead chelators and the iron
supplements correct this issue (7,38).
Many studies have shown the connection between iron
deficiency anemia and later cognitive deficiencies. Lozoff et
colab. (2006) have shown the cognitive deficiencies in the
1-2 decades after iron deficiency during the baby stage (18).
Nevertheless, it is difficult to determine a causality
connection. It is known that iron is essential in neurological
development. The iron deficiency affects the neuronal
metabolism, the neurotransmitter metabolism, the
mielinisition and memory (6,11,30). These observations
could explain the behavioral problems in children with iron
deficiency.
Paraclinical diagnosis
We follow certain parameters: the hemoglobin
concentration, the reticulocites, erythrocitary indexes, the
total iron assimilation, the transferrine saturation,
protoporphyrine, ferritine and sTfr (transferrine receptor).
The last parameter, the soluble form of the transferrine
receptor that freely travels into the plasma, is an important
indicator of the status of iron in the organism.
In this table we show the changed in the main
parameters.
Parameter
Iron deficiency without Iron deficiency anemia Iron overload
anemia
Ferritine ↓ ↓↓ ↑
Transferrine saturation ↓ ↓ ↑↑
Transferrine receptor ↑↑ ↑↑↑ ↓
(sTfr)
Reticulocitary hemoglobin ↓ ↓ Normal
Hemoglobin normal ↓ Normal
VEM normal ↓ normal
↓ low value, ↑ high value
The iron status in children is not determined by a simple
determination of hemoglobin concentration. The decrease in
hemoglobin can have a variety of causes, of which we
mention the hemolitical anemia, the chronic disease anemia,
the B12 or folic acid deficiency anemia, the genetic disease
anemia. But once put the iron deficiency diagnosis, the
supervision of the hemoglobin concentration is a good
response measure to the treatment.
Any set of analysis will include the hemoglobin
concentration to determine whether or not there is anemia.
The three parameters giving selective data about the status
of the iron are: ferritine, reticulocitary hemoglobin and the
transferrine receptor.
Ferritine is a sensitive parameter for the assessment of
the iron deposits in healthy subjects (1 µg/L of ferritine
corresponds to 8-10 mg of available iron). In children the
value showing the depletion of the iron deposits is of 10
µg/L (in adults 12 µg/L) (9,17). Because the serum ferritine
is a short phase reactant, its concentration can be increased
in the presence of chronic inflammations, infections,
malignancies, hepatic diseases. A simultaneous
determination of protein C reactive is needed to exclude the
inflammation.
Even though serum ferritine has a lower accuracy that
reticulocitary hemoglobin or the transferrine recepton, the
combination of ferritine and protein C reactive is more
accessible and a more reliable test as long as the protein C
reactive is not high (9,17,34).
The reticulocitary hemoglobin and the transferrine
receptor are not influenced by the inflammation,
malignancy, infections, chronic diseases and are preferable
for the diagnosis. The reticulocitary hemoglobin has been
validated, standardized in children and actually available.
This parameter provides a measurement of the available iron
in the cells recently released by the bone marrow (5). The
reticulocitary hemoglobin can be measured by citometric
flow and the low concentration is the most important in
predicting iron deficiency in children.
The transferrine receptor (sTfr) is a measure of the iron
status which finds the iron deficiency on a cellular level
(32,37). It is found on the cell membrane and allows the
transfer of iron in the cell. When the iron is insufficient,
there is an imbalance of the transferrine receptor’s
permission for the cell to have a more efficient iron
composition and later its circular form has a serum increase.
An increase in serum in the transferine receptor can be
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JURNALUL PEDIATRULUI – Year XIV, Vol. XIV, Nr. 53-54, january-june 2011
found in the patients with iron deficiency or iron deficiency
anemia, even though the serum doesn’t increase until the
iron deposits are depleted in the adults. The assessment of
the transferrine receptor is not usually available and the
standard value for children has not yet been established.
For putting the diagnosis of iron deficiency anemia
(when a hemoglobin value smaller than 11g/dl is
associated), nowadays the following tests can be used:
ferritine + protein C reactive or reticulocitary hemoglobin.
For the iron deficiency diagnosis without anemia the same
parameters are measured.
Another approach in the diagnosis of iron deficiency
anemia in mild anemia children (Hb 10-11g/dL) is the
monitoring of the response to iron supplements, especially if
the history of the nutrition involves an iron-poor diet. An
increase in hemoglobin of 1 g/dL after 1 months of
treatment is used as positive for iron deficiency anemia.
This approach imposes an adequate iron treatment, the
compliance of the patient and an adequate absorption.
Correcting the iron deficiency and iron deficiency anemia.
Premature babies. The naturally-fed premature babies
(below 37 weeks of gestational age) will receive elementary
iron supplements of 2 mg/kg/day beginning with 1 month of
age until 12 months. The iron can be provided through
medication or through an iron-rich diet. The premature
babies who are fed with formulae for premature babies (14.6
mg iron/L) or ordinary formulae (12 mg iron/L) will receive
approximately 1.8-2.2 mg/kg/day assuming a milk
consumption of 150 ml/kg/day (12,29).
Despite the iron-enriched formulae, 14% of premature
babies have an iron deficiency between 4 and 8 months of
age. Thus the enriched formulae need an iron supplement
addition. The exception for these iron supplements are the
premature babies who received multiple transfusions during
the hospitalization period, who might not need iron
supplements.
Naturally fed full term babies. The full term baby has a
higher hemoglobin concentration and a higher blood volume
as compared to body weight. They go through a
physiological decrease in hemoglobin and blood volume
during the first four months of life. Usually the iron deposits
are enough for the first 4-6 months. The iron content of
human milk is enough for the newborns who are exclusively
naturally fed.
The exclusively natural diet is recommended for 6
months. The exclusively natural diet for the newborns after
6 months is connected to a higher risk of iron deficiency
anemia at the age of 9 months. The recommendation for an
exclusively natural diet does not take into account the babies
born with low iron deposits (the newborns with a low
weight at birth, the babies whose mothers have diabetes), a
situation which also determines a low iron concentration at
the age of 9 months.
It is recommended that the full term babies who are
exclusively naturally fed receive an iron supplement of 1
mg/kg/day starting with the age of 4 months until the
introduction of the iron-rich foods (10,25).
For the mixed-fed babies, the proportion of the breastfeeding
as opposed to the formulae is uncertain. Thus, after
4 months the babies who do not receive an iron-rich diet will
get 1 mg/kgc/day supplemental iron.
Artificially fed full term babies. The American Pediatric
Association has concluded that the milk formulae containing
12 mg elemental iron /L are safe (26,27,31). There is not
enough data to relate the formulae with 12 mg/L to the
gastro-intestinal symptoms (3,12,31).
Small children (1-3 years). The necessary iron in small
children is of 7 mg/day. Ideally, the necessary iron must be
provided through food naturally rich in iron and vitamin C
which stimulates the iron absorption. In the developing
countries, the necessary iron is covered by the iron
strengthening of certain foods such as corn flour, soy sauce,
rice, cereal. Nevertheless, there are barriers to providing an
optimal iron intake: the lack of education of the parents, the
low compliance to any digestive adverse effects, the price of
enriched products, the federal nutrition programs which do
not provide iron supplements. In the US, the iron-enriching
of formulae and cereals for the babies has lead to the
decrease of iron deficiency anemia (2).
As an alternative for those who do not take enough iron
from the diet, there are also the iron supplements which are
available as a component of the multivitamin syrup or
chewable tablets (4,13,14).
Screening for iron deficiency and iron deficiency anemia.
The universal screening must assess the risk factors
associated to the iron deficiency/iron deficiency anemia: a
history of premature birth or small weight at birth, exposure
to led, an exclusively natural diet over 4 months without
iron supplements, an integral milk diet, a diet of non-iron
enriched cereal or of low-iron foods. The additional risk
factors include nutrition problems, an inadequate diet, a
stationary weight curve.
In the US 60% of the anemia cases are not due to the
iron deficiency and most of the iron deficiency children do
not have anemia.
Selective screening tests can be done at any age when
the risk factors for iron deficiency and iron deficiency
anemia are found.
After determining the hemoglobin concentration, in
children with hemoglobin below 11 mg/dL or with a high
risk of iron deficiency the ferritine + protein C reactive and
reticulocitary hemoglobin are determined. The
determination of the transferrine receptor will enter the
screening tests once the value in children is determined.
Conclusions
It is important that we eliminate the iron deficiency and
iron deficiency anemia in babies and young children,
considering their impact on cognitive and behavioral
development(22,24,30). There are controversies regarding
the time and methods of screening and on the use of iron
supplements.
The present data support the following
recommendations:
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• Healthy newborns born on time have enough iron for at
least the first four months of life. The exclusively natural
feeding after the first four months without iron supplements
leads to an iron deficiency. The naturally fed babies must
receive 1 mg/kg/day starting with the age of 4 months until
the iron-rich foods (including cereal) are introduced in the
diet.
• For the mixed-fed babies, the proportion of mother milk
vs. formula is uncertain. Consequently, starting with the age
of 4 months the mixed-fed babies who do not receive ironrich
foods must receive 1 mg elemental iron/kg/day.
• For the formulae-fed babies, the necessary iron can be
covered by standard milk formulae (iron content 10-12
mg/L) and the introduction of foods containing iron after 4-6
months of age, including cereal. The integral milk must not
be used before 1 year of age.
• The iron addition between 6 and 12 months must be of 11
mg/day. When the food becomes more varied, the
vegetables and red meat with a high iron content are
introduced. If the food does not cover the necessary, the
liquid iron supplements will be introduced.
• The small child (1-3 years) has a necessary of iron of 7
mg/day which will be provided by the red meat, ironenriched
cereal, iron-rich vegetables, fruit with vitamin C
which increases the iron absorption (35,36). In the case of
the children who do not receive the appropriate iron-rich
food, iron supplements are recommended as syrup or
chewing tablets.
• Premature babies must receive an iron addition of at least 2
mg/kg/day until 12 months old, including the supplementary
iron in the milk formulae. Naturally fed premature babies
must receive iron supplements of 2 mg/kg/day after 1
months of age until the diversifying with iron-rich foods
(29). The exception consists of the premature babies who
have received iron through blood transfusions and
erythrocitary mass transfusions.
• The universal anemia screening must be done at
approximately 12 months with the determination of the
hemoglobin concentration and the assessment of the risk
factors related to the iron deficiency/ iron deficiency
anemia. These risk factors include precarious socioeconomic
status, a history of premature birth or small
weight at birth, exposure to led, exclusively natural nutrition
until 4 months of age without iron supplements, iron-rich
foods and iron-enriched cereal. Additional risk factors are
the eating disorders, inadequate weight gain, inadequate
nutrition. In the case of babies and small children, the
screening must be done whenever the risk factors are
involved.
• If the hemoglobin level is less than 11 mg/dL at 12 months
the cause of the anemia will be investigated. If there are risk
factors of iron deficiency the status of the iron will be
investigated. The ferritin + reactive protein C and
reticulocitary hemoglobin will be determined. Afterwards
the correct treatment will be applied.
• If a child has mild anemia (Hb 10-11 mg/dL) and can be
closely monitored, an alternative diagnosis method will be
the increase by 1g/dl of the hemoglobin concentration after a
month of iron therapy.
• The use of the transferrin receptor (sTfs) as screening
for the iron deficiency is promising and the establishing of
the standard value is expected for the use on babies and
small children.
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Correspondance to:
Carmen Elena Niculescu
Petru Rares Street, No. 3,
Craiova, Romania
E-mail: niculescudragos@yahoo.com
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